Diesel engine starter



Aug. 5, 1969 BENDER ET AL DIESEL ENGINE STARTER 2 Sheets-Sheet 1 Filed Aug. 22, 1967 INVENTOR'S. DONALD E. BNDER JAMES KAYTOR LOWELL LRUSS'L ATTORNEY 2 Sheets-Sheet 2 Filed Aug. 22, 1967 m u mMRfi NMS VMY N .A EKL 0 m M M MMW m @N% W Y B fin R W Q Qmw QM V:

ATTORNEY United States Patent 3,459,165 DIESEL ENGINE STARTER Donald E. Bender, Herrin, James Kaytor, West Frankfort,

and Lowell L. Russell, Herrin, Ill., assignors to Olin Mathieson Chemical Corporation, a corporation of Virginia Filed Aug. 22, 1967, Ser. No. 662,421 Int. Cl. F02n 7/08, 13/00 US. Cl. 123-179 9 Claims ABSTRACT OF THE DISCLOSURE This invention relates generally to a starting system for starting engines. More particularly it relates to a combined cartridge and air starter for use in starting diesel engines, internal combustion engines, and turbine engines.

It is contemplated that this invention will be used most extensively in connection with diesel engines and, therefore, the description of the preferred embodiment will be discussed in connection with such an engine.

There are three generally accepted methods of starting a diesel engine. These methods involve either an electric starter, a hydraulic starter or an air starter.

The electric starter usually consists of a 12-volt battery and a 12-volt starting motor along with suitable auxiliary components. Although an electrical starting system has many attractive attributes it is not without its limitations. One of the common complaints is a dead battery. During cold weather operations battery power output decreases rapidl and at low temperatures the battery is very hard to charge. Moreover, in the case of the larger, more powerful diesel engines the l2-volt starter is not sufficient. To remedy this, starter manufacturers have produced a 24-volt starting motor. However, in order to use this with a 12-volt electrical system on the truck, it is necessary to use a series parallel switch. During the starting operation this switch automatically places two 12-volt batteries in series to power the starter. During the remaining time, the series parallel switch places the two 12-volt batteries in parallel to power other electrical components on the truck and to accept a charge from a 12-volt generator. However, it has been found that the series parallel switch has a high malfunction rate and that the 24-volt motor is not vastly superior to the 12-volt version.

The cold weather itself causes starting problems in connection with an electrical starting system. In cold weather the viscosity of the engine crankcase oil increases. Since the power output of a battery drops in cold weather, and in cold weather the required cranking power is the highest due to the increase in the viscosity of the oil, the available cranking power from the batteries may be too low to start the diesel motor.

The second type of starting system uses hydraulic pressure to power the starting motor. The main components of such a system are a hydraulic pump driven by the engine, a hand operated pump for emergencies, and an accumulator, a starting motor, and a reservoir. The accumulator is constructed so that the hydraulic fluid exerts force on a piston which in turn compresses nitrogen on ice the other side of the system at a pressure of about 3,200 psi. This then provides the stored energy for starting. It has been found, however, that such units are not generally acceptable for use on over-the-road trucks because of the complaint that frequent use causes seal leakage in the starter motor.

Air starting systems are gaining in popularity especially in those applications where weight is important as it eliminates the need for heavy batteries. In its basic form, an air starting system comprises an air reservoir whose volume may be from 30 to 60 gallons which is pressurized by the air brake compressor on the truck. The reservoir is connected by suitable plumbing through a quick-release valve to a vane air motor which is used to drive a starter pinion gear which engages with a gear on the truck connected to the engine. Air starting, however, is not without its limitations since only a limited supply of air is available. If the start is not accomplished on the first try and the driver cranks the engine intermittently the tank pressure will fall below the value required for getting the starter motor and truck engine into motion. In addition, it has been found that if a truck sits overnight there is a tendency for the air to leak out of the reservoir whereby the air pressure available in the morning will not be sufficient to provide the required cranking power. Although air starting overcomes some of the problems that have plagued the electrical system in cold weather, some operators complain that condensation from the air in the tank and piping system may find its way into the starting motor and freeze the vanes in place at low temperature.

The present invention is directed to providing a back up system for use with an air starter. In the event that an air starter fails for one reason or another the back up system includes the provision of a gas-generating cartridge capable of generating high pressure gases which can be used for powering the same starter motor which is used for air starting.

In view of the above, it is an object of this invention to provide an improved starting system for an engine.

Another object of this invention is to provide a more reliable starting system for engines. Yet another object of this invention is to provide a starting system for a diesel truck which is effective at low temperatures.

More specifically, it is an object of this invention to provide a combined cartridge and air starter, including a starting motor, which can be powered either by compressed air or by the gases generated from a gas-generating cartridge.

Yet another object of this invention is to provide a starting system for a diesel engine wherein compressed air is normally used to crank the starting motor, but wherein a gas-generating cartridge can be used in the event the required air pressure is not available.

These and other objects of the invention will become more apparent by reference to the following description and to the accompanying drawings in which:

FIGURE 1 is a schematic diagram of the combined cartridge and air starting system adapted to be used on an over-the-road diesel truck;

FIGURE 2 is an enlarged View, partially in section, of the cartridge receiving chamber and breech mechanism;

FIGURE 3 is a side view, partially in section, of the starter motor assembly;

FIGURE 4 is a sectional view taken along the lines 3-3 of FIGURE 3; and

FIGURE 5 is a sectional view of a lubricator for use in the system shown in FIGURE 1.

Referring to the drawings and specifically to FIGURE 1, the air starting portion of the starting system of this invention may comprise an air receiver or reservoir 2 which may be mounted on the truck in some convenient location. The air reservoir 2 is provided with an inlet conduit 4 which is connected to a compressor (not shown) mounted on the truck. The reservoir 2 is charged by the compressor, which is driven by the engine of the trucks, to a pressure which is usually in the range of from about 100 to 120 p.s.i. maximum. The inlet conduit 4 is usually provided with a one-way check valve 6 to permit flow into the receiver 2 while prohibiting flow out of the reservoir 2. A safety valve 8 communicates with the interior of the reservoir to prevent overpressurization of the receiver 2. An emergency fill valve 10 communicates with the air receiver 2 so that the air receiver 2 can be filled from an outside source of compressed air if such a source is available. A drain valve 12 extends downwardly from the bottom of the air reservoir 2.

A quick-acting, on-off, high capacity valve 14 has its inlet port connected to the outlet of the air reservoir 2 and its outlet port connected to the main air conduit 16. The valve 14 may be of the type which can be actuated manually, pneumatically htrough an air pilot system, or electrically. In the case shown in FIGURE 1, an actuation switch 18 is connected by suitable wiring 20 to the valve 14 and also to a source of electrical power such as a battery (not shown) whereby actuation of the switch 18, which can be positioned in the truck cab in easy access to the driver, will open the valve 14.

The cartridge portion of the starting system comprises a cartridge receiving chamber 22 provided with a high pressure safety disc 24 of a type well known in the art to let the gases escape in the event of overpressurization in the high pressure section.

The cartridge receiving chamber 22 also includes a removable breech closure 26 containing a suitable firing mechanism (not shown) capable of igniting the cartridge assembly 28. The firing mechanism may include a firing pin which is electrically operated by virtue of an actuating switch 30 connected to the firing mechanism by suitable wiring 32 and to a source of electric power such as the battery of the truck. The actuating switch 30 may be positioned in the cab of the truck.

The cartridge assembly 28 may comprise a packaged unit including a low energy solid propellant and an ignition device contained within a hermetically sealed metal container. A conventional primer may be provided for igniting an ignition device which in turn ignites the solid propellant.

A nozzle 34 is provided adjacent the end of the cartridge receiving chamber 22 to reduce the pressure of the gases as they enter the hot gas conduit 36. A low pressure safety disc 38 is positioned in the hot gas conduit 36 immediately downstream of the nozzle 34 to prevent overpressurization in the hot gas conduit 36. The main air conduit 14 and the hot gas manifold 36 join together at a T-shaped connection 40 immediately above the starter assembly 42. The main air conduit 16 is provided with a check valve 44 adjacent the connection 40 to prevent gases from the cartridge from flowing up to the air valve 14.

A starter lubricator 46 is provided to supply lubricant to the stream of hot gases or compressed air as they enter the starter assembly 42 to insure proper lubrication of the moving parts of the assembly. A first conduit 48 extends from the inlet portion of the starter assembly 42 to the lubricator 46 to bleed either the compressed air or hot gases from the inlet to actuate the lubricator 46. A second conduit 50 extends from the lubricator 46 to the inlet portion of the starter assembly 42 to provide for flow of the lubricant to the starter assembly 42. A third conduit 52 extends from a lubricant reservoir (not shown) to the lubricator 46 to provide a means for refilling the lubricator 46 after each starting operation.

A starter assembly 42 that has been found to be compatible with both an air start and a cartridge start is shown in FIGURES 3 and 4. The assembly 42 comprises a vane motor 54 and a drive assembly 56. The vane motor 54 comprises an outer housing 58, a rotor casing 60 having .a cylindrical inner surface 62 and a rotor 64 mounted eccentrically with the axis of the cylindrical inner surface 62 of the casing 60. The outer housing 58 includes a main inlet 66 to which the outlet end of the T-shaped connection 40 is attached. The inlet 66 communicates with passages 68 in the rotor casing 60 which in turn communicate with the interior of the rotor casing 60 defined by the cylindrical inner surface 62.

The rotor '64 is provided with a series of circumferentially spaced, longitudinally extending slots 70 in which are mounted vane members 72 which are movable radially inwardly and outwardly in their respective slots 70. Each of the vane members 72 are biased outwardly by means of a spring member 74 mounted between the bottom of the slot 70 and the base of the vane member 72. Since the motor must be compatible for use with a gasgenerating cartridge wherein the temperature of the gases entering the motor may be in the magnitude of between 1000 F. to 1200 F., the vane members 72 must be constructed of a material capable of withstanding repeated exposures of short intervals of gases at these temperatures. After a great deal of experimentation, it has been found that one such material is a polyimide of the type manufactured under the trademark Vespel and which contains about 15 percent graphite. The rotor casing 60 also includes an exhaust port 76 which communicates with an exhaust outlet 78 in the housing.

The rotor 64 of the vane motor 54 is attached to the drive assembly 56 by means of a gear 80 driven by the rotor 64 which engages with a gear 82 on the shaft 84 of the drive assembly 56. The drive assembly 56 is contained within a suitable housing 86 and includes starter engaging means 88 for causing the starter gear 90 to engage the gear 92 connected to the diesel engine when the vane motor 54 is actuated. The starter engaging means 88 may be of the conventional type wherein a friction clutch is provided to cause the starter gear 90 to move into engagement with the gear 92 connected to the engine upon rotation of the drive shaft 84. Some typical starter engaging means are shown in US. Patent Nos. 3,003,006, 3,222,938 and 3,263,509.

A starter lubricator 46 particularly adaptable for use with the above-described combined air and starter system is-shown in FIGURE 5. The lubricator 46 comprises a housing '94 in which a piston 96 having a first portion 98 of a smaller diameter and a second portion 100 of larger diameter is contained for limited movement. An inlet port 102 for either the air or hot gases to which the conduit 48 is attached is provided in one end of the housing 94 and communicates with a chamber 104 at the rearward end 106 of the piston 96. When the piston is in its rearwardmost position, the chamber 104 is initially formed by a recess cut into the rearward end 106 of the piston 96.

An outlet 108 is provided at the opposite end of the housing in front of the smaller diameter portion 98 of the piston 96. The conduit 50 is connected to this outlet 108 and includes a check valve 110 positioned in the conduit 50 immediately adjacent the outlet 104 to permit flow only in the direction from the lubricator 46 to the starter assembly 42.

The smaller diameter portion 98 of the piston 96 includes a forward face 112 which has an axially extending bore 114 therein. A spring member 116 extends between the base of the bore 114 and the housing 94 to urge the piston 96 toward its rearward position as shown in FIG- URE 5. The bore 114 and the area in front of the smaller diameter portion 98 of the piston 96 form a chamber 118 for receiving lubricant from the lubricant reservoir through an inlet 120 provided in the housing. The conduit 52 from a lubricant reservoir (not shown) is connected to the inlet 120 and includes a check valve 122 which permits flow only in a direction into the chamber 118. Neither check valve 110 nor check valve 122 have been shown in detail as such devices are well known in the art.

In operation, if an air start is desired, the operator merely actuates the quick-acting, on-olf valve 14 which permits the compressed air in the air reservoir 2 to flow through conduit 16, connection 40, to the inlet 66 of the starter assembly 42. The air passes through the passages 68 in the rotor casing 60 and enters the interior thereof where it acts against the vanes 68 on the rotor 60 and rotates the rotor 60 in a counterclockwise direction as viewed in FIGURE 3. The rotation of the rotor 60 rotates the shaft 84 of the drive assembly 56 setting the drive assembly 56 into operation whereupon the drive pinion 90 engages with and rotates the gear 92 connected to the engine of the diesel motor.

At the same time the compressed air enters the starter assembly 42, a portion of the air is bled off through the inlet conduit 48 to the starter lubricator 46. The high pressure air acting on the rearward end 106 of the larger diameter portion 100 of the piston 96 forces the piston 96 toward the outlet 108 causing a portion of the lubricant contained within the chamber 118 to flow through the outlet conduit 50 to the starter assembly 42 and become entrained in the stream of high pressure air. When the start has been accomplished and the supply of high pressure air cut off, the spring member 116 returns the piston 96 to its original rearward position and in so doing, draws in a measured amount of lubricant through the conduit 52 from the lubricant reservoir and check valve 122 whereupon the lubricator is ready for the next start.

It is to be noted that during the operation of the lubricator 46, as the effective area of the rearward end 106 of the piston 96 is greater than the effective area of the forward face 112 of the piston, the high pressure gases acting upon the rearward end 106 will exert a greater force on the piston than the opposing force on the forward face of the piston due to the lubricant having to act against the pressure of the gases in conduit 50. Thus, the piston 96 will be moved toward the outlet 108 to force the lubricant through conduit 50 into the inlet 66 of the starter assembly 42. Also, the check valve 122 prevents lubricant from entering the conduit 52 during the forward operating stroke of the piston 96. The check valve 110 prevents air from being drawn into chamber 118 from conduit 50 during the return movement of the piston 96.

In the event a cartridge start is desired, all the operator is required to do after the cartridge assembly 28 has been placed in the cartridge receiving chamber 22 and the breech closure 26 secured thereto is to actuate the switch 30 in the cab of the truck which in turn will ignite the cartridge generating high pressure gases. These gases will flow through the nozzle 34, conduit 36 and connection 40 to the inlet 66 of the starter assembly 42 whereupon the gas will act upon the vane motor 54 and actuate the drive assembly 56 in the same manner as described in connection with the high pressure air. In addition, a portion of the hot gas will bleed oil? through conduit 48 and act upon the starter lubricator in the same manner as the high pressure air and supply lubricant to the stream of hot gases entering the starter assembl 42.

To enable the two systems to be compatible with a single starting motor 44 it has been found necessary to reduce the temperature of the gas from their high temperature immediately forward of the cartridge receiving chamber 22 to a lower temperature when they enter the motor 44. By way of an example, the temperature range of the gases as they leave the cartridge receiving chamber 22 may be between 2050 F. and 2150 F. This would cause serious deterioration of the vanes and other working parts of the motor if the gases entered the starter assembly 42 at this temperature. One method of regulating the temperature is through the length of the hot gas supply conduit 36, the length should be such that it is long enough to insure that some heat transfer to the atmosphere will take place so that the gas is not too hot and short enough so that the gases do not lose their energy. It has been found that if thin-walled stainless steel tubing has a wall thickness of .060 inch and an internal diameter of .50 inch the length of the conduit 36 should be between 7.5 and 11 feet. If the conduit is kept within this range, no additional heat dissipation means is necessary. This is advantageous in that such means would add to the overall weight of the unit. If standard heavy duty one inch stainless steel pipe is used the length of the conduit can be shortened by about two feet. If it should be necessary, due to limitations imposed by the design of the vehicle, to shorten the length of the conduit 36 below the above-mentioned lengths, then a heat sink or some other means for heat dissipation must be included to reduce the temperature of the hot gases.

By virtue of the above-described arrangement a system is provided wherein a cartridge start can be substituted without requiring a separate motor or driving assembly. The above-described system is relatively inexpensive to manufacture, simple in construction and light in weight, yet insures a proper start to all circumstances.

While reference has been made above to a specific embodiment of this invention, various modifications and alterations will readily suggest themselves to those skilled in the art. Accordingly, the scope of this invention should be ascertained by reference to the following claims.

What is claimed is:

1. A starting system for engines comprising a starter assembly including a vane motor having an inlet and a drive mechanism adapted to be actuated by the vane motor to impart power to the engine, an air reservoir for storing compressed air, conduit means connecting said air reservoir to the inlet of said starting motor, a cartridge receiving chamber adapted to receive a gas generating cartridge, breech means closing said cartridge receiving chamber, and gas conduit means connecting said cartridge receiving chamber to said inlet of said vane motor, air valve means in said air conduit means for permitting flow in said air conduit when said valve is opened, and cartridge actuating means in said breech means.

2. The system of claim 1 wherein said air conduit means and said gas conduit means join together before entering said inlet, and said air conduit mean is provided with a check valve between said air valve means and said connection to permit flow in the direction from the air reservoir to the vane motor while prohibiting flow in the opposite direction including the flow of gases to the air valve.

3. The starting system of claim 2 further including lubricator means, said lubricator means including means operable upon the influence of the compressed air or hot gases to supply a predetermined amount of lubricant to said inlet of said vane motor.

4. The starting system of claim 2 further including nozzle means positioned adjacent the cartridge receiving chamber to reduce the pressure of the hot gases generated in the cartridge receiving chamber as they flow into the gas conduit.

5. The starting system of claim 4 further including means for reducing the temperature of the gases generated by the cartridge from their temperature at the nozzle means to a lower temperature at the point where the gases enter said inlet.

6. The starting system of claim 4 wherein said gas conduit means comprises thin-walled, stainless steel tubing having a wall thickness of about .060 inch and an internal diameter of about .50 inch and a length of between about 7.5 and 11 feet.

7. The starting system of claim 4 wherein said gas conduit comprises standard heavy duty one inch stainless steel pipe having a length between about 5.5 and 9 feet.

8. The starting system of claim 2 wherein said vane motor comprises a housing having an inlet, a rotor casing having a cylindrical inner surface, and a rotor having an axis eccentric with the axis of said inner surface, said rotor having a plurality of axially extending, circumferentially spaced slots, a rotor blade mounted in each of said slots, means biasing each of said blades radially outwardly into engagement with said inner surface, and means connecting said inlet to the interior of said rotor casing so that either the gases from the gas generating cartridge or the compressed air can impinge upon said rotor blades to drive said rotor.

9. The starting system of claim 8 wherein said rotor blades are fabricated from a polyamide containing about 15% by weight graphite.

References Cited UNITED STATES PATENTS 10 WENDELL E. BURNS, Primary Examiner US. Cl. X.R. 

